The purpose of this project is to investigate the role of the central nervous system in behavior. In some experiments we examine the contribution of somatic factors in instrumental cardiovascular conditioning (ICC). Brain areas of special interest are the hippocampus, caudate nucleus and pyramidal tracts. Subjects are monkeys (Macaca mulatta). We also examine the quantitative and qualitative nature of the constraints that can be placed on the animal during ICC. Thus far, two procedures have been utilized. In the first electrical stimulation is administered to localized CNS cardioacceleratory-pressor or cardiodeceleratory-depressor sites, e.g., hypothalamus. In a second procedure animals are trained to perform on a food-reinforced exercise task and then ability to control heart rate during combined exercise and ICC sessions is examined. In other experiments we examine age-related changes in pre- and post synaptic portions of nigrostriatal pathways using behavioral and biochemical analytical methods. The present topics include possible alterations in: development of post synaptic denervation hypersensitivity, (b) specificity and affinity of dopamine receptor binding, (c) adenyl cyclase production and (d) synaptic release mechanisms that might occur with age.